Notes on the History of the Giffen Paradox

FOR more than half a century economists have recognized the possibility of a positively sloping demand curve. They have desired a real example, probably to reassure themselves of the need for discussing the possibility, and almost invariably they have used Marshall's Giffen paradox as this example. The present note arose out of curiosity as to the nature of the evidence for the paradox-a curiosity that was and is far from satisfied. Marshall introduced the paradox in the third edition of his Principles (I895),' with a paragraph that was not changed in essentials in later editions: